ALK and non-small cell lung carcinoma: The 73 patients with ALK-positive advanced NSCLC were divided into three groups based on the first-line treatment: first-line crizotinib group (1-CRZ group, n = 32); first-line platinum-based pemetrexed treatment group (1-PP group, n = 28), and first-line chemotherapy platinum-based non-pemetrexed group (N1-PP, n = 12).